Buffer



Feb. 6, 1951 G. R. MUNRQ BUFFER Filed OCT.. l1, 1947 ATTORNEYS atented Feb. 6, 1,951A

UNITED STATES'.

MENT oF-FICE slclaim-s.

This invention: relates to buiersl for use on railvv'ay'rolling stock and is concerned-more' particularly` with a n'ovel buienthe elements of which are held in"assembledy relation byv interiengaging parts and Without the use of bo'lts or other fastening devices; The new` buffer is; accordingly, of simplified construction and assembly and it-has the "form'of' a-self-containedunit. The builerincludes spring means and Fig. 1 isa longitudinal sectional view-through onelform of the newbuffer;

Figs. 2 to 6, inclusive, are sectional-views on the lines 2 2,v 3 3," ii-4, 5:'-5,' and 'ii- 5, respectively, of Fig. l; and

Fig.' 7 isa fragmentary.v rear end view-of the buffer showing a-lockingmeans in' inoperative position.

The buffer in the form illustrated inthe accompanying drawing includes ahousingof generallyV tubular form having one end closed. The

housing may be of unitaryconstructionfbut preferably consists of abase' plate it and-af'tubular section H secure'd'to the base-plate by Welding. At its open end, the tubular section ofthe housing is formed with circumferentiallyspaced inward projections, which may be conveniently formed by indenting the metal of'the section' at spaced places, as indicated at i2. The base plate projects outwardly beyond the end 'of the tubular section and may be of oblong form and provided with openings I3, through which bolts or other meansfor attaching the buffer to the car structure may be passed.

The buffer includes a main plunger which, in the form illustrated, comprises a length ofvtubing lli closed at one end by a head l5 of dished form Welded to the end of the tubing. At its open end, the tubing is provided with circumferentially spaced outwardprojections I6, which may be conveniently formed'by expanding the' end of the tubing at" spaced places by appropriate means. rlhe formation of the projections onv the tubing in this manner produces circumferentially spaced recesses in the inner surfaceof` the tubing, each recess being dened at its ends by substantially radial shoulders; 'I'he outer diameter of tubing I4 inward"from'projections |6` is slightly less than the internaldiameter'ofthe housing across thefinWard projections l2' thereon, and the dimensions and spacing of the inward projections l2 on the housingv and the outward projections l'on the plunger are such that, when the plunger and housing are in proper angular relation, the open end of the plunger may be inserted into the housing, with the plunger projections passing between the housing projections. Thereafter, the plunger may be rotated through a small angle to bring its projections behind those on the housing, after which the engagement off the projections on the housing. and plunger' limits the movement of the plunger out of the housing.

An inner plunger is mounted loosely within the main plunger and preferably comprises a tube H closed at one end by a dished head i8 Welded to the tube. The curvature of the inner plunger head is similar to that of the head i5 of the main plunger, so that the head of the inner plunger may seat against the head of the main plunger and make extended contact therewith. The head I8 of thev inner plunger is of substantially greater diameter than the tube I1 and, at'its inner end, the tube is formed with a section I'Ia, of diminishing outer diameter toward the open end of the tube.

The movement of the main and inner plunger into thehousing is resisted byv friction means, which may` takevarious forms, but, in the constructiondisclosed, include a ring E9 loosely encircling the tube IT of the inner plunger adjacent its tap'eredend. @ne face of the ring is at and the other end is inclined to the axis of the-plunger. The inclined face ofthe ring bears against similarly. inclined faces of a group of friction shoes 20, which encircle Ytube il and contact on their-inner surfaces with the tapered surface of the tube il.' In the construction illustrated, there are three shoesy 2d" and, at their ends adjacent the endoftube il, the shoes have inclined surfaces which bear against a similarly inclined surface on one end off a cylindrical block 2|. The block 21 isclosed at its opposite end by a plate 22, which has a projection' 23 extending outivardly'therefrom. The projection is oifnon-'circular outline and, in the construction shown, has corner extensions 23a, so that the overall shape'oi? projection is approximately thatvof a square; The base plate it has a central opening' ma, into which projection 23'Y on plate 22V mayl be inserted and, when the projection-lies Within opening ida, block 2i is held against rotational movement relative to the base'l.

The block 2l extends into the" op'enl end' of tubing lli of thevmainplunger and has longitudinal projections il, which enter the grooves formed by expansion of the end of the tubing to provide the outward projections I6. The lateral edges of the grooves form stops, with which the projections 2:3 on block 2l may engage, and the interengaging parts prevent rel-ative rotational movement of the main plunger and block, while permitting free longitudinal movement of the plunger. When the projection 23 is seated in opening Illa, the projections 2li on block 2! hold the main plunger with its projections I6 aligned with and behind the inward projections l2 on the housing.

Spring means are disposed within the main plunger and housing to bear at one end against the head I8 of the inner plunger and hold that plunger against the head l of the main plunger. At the other end, the spring means bear against ring I9 and maintain the elements of the friction means in contact. The pressure of the spring means against ring i9 is transmitted through the inclined surfaces of the ring and the shoes 2t to hold the shoes in tight contact with the outer surface of tube l'l. In the construction discosed, the spring means take the form of a heavy coil spring 25 and, when force is applied to the buer to move the plunger into the housing, such movement is limited by means of a collar 2E encircling the tube lll of the main plunger outside the housing and at such a distance from the end of the housing that the collar strikes the end of the housing and arrests the movement of the main plunger into the housing before the coils of spring 25 make contact with one another.

In the assembly of the buffer, the block 2l is placed within the housing with its projection 23 angularly misaligned with opening lila through the base plate le and bearing against the inner face of the base plate adjacent the opening. The shoes 2G are then placed in contact with the inclined surface of block 2l, ring I9 placed on the shoes, and spring 25 is placed upon ring I9. The inner plunger is then inserted through the spring with its tapering end passing through the group of shoes. The main plunger is next oriented to align its outward projections l with the spaces between inward projections l2 on the housing and then telescoped over the spring and inner plunger. plunger to move its open end into the housing against the resistance of spring 25. When the main plunger has been moved into the housing until its projections l5 lie inward from the inner ends of projections l2 on the housing, the end of tubing l of the main plunger will have telescoped over the end of block 2| and the projections Zll on the block will lie between the stops formed by the sides of the expanded portions of tubing I4, which form projections i6. The main plunger is then turned angularly through a small arc, until the projection 23 slips into the opening ma. In that reation of the parts, the outward projections l5 on the main plunger lie behind the inward projections l2 on the housing and, when the plunger is released, it will be forced outwardly from the housing by spring 25, until the engagement of projections l2 and i6 prevents further movement. The buffer is now in condition for use and the plunger is free to be moved longitudinally relative to the housing by forces applied to the main plunger head.

Angular movement of the main plunger relative to the housing during use of the bulfer is prevented by the interengagement of block 2| of Force is now applied to the main the friction means with the stops on the inside of the inner end of the plunger and by the interengagement of projection 23 with the walls of opening l on the base plate of the housing. Whenever it is desired to disassemble the buffer, a tool is applied through opening la against projection 23 and block l is moved inwardly into the housing, until the projection is clear of the opening. With the parts in this condition, the main plunger may be rotated until its projections I6 are in alignment with the spaces between the inward projections I2 on the housing. Thereupon, the main plunger may be withdrawn from the housing by longitudinal movement.

I claim:

1. A buffer comprising a housing open at one end and closed at the other and having circumferentially-spaced inward projections at its open end, a hollow main plunger extending through the open end of the housing, the plunger having a closed outer end and circumferentially-spaced outward projections and circumferentially-spaced internal shoulders within the housing, the plunger projections normally being engageable behind the inward projections of the housing to limit the outward movement of the plunger from the housing when the plunger and housing are in one angular relation, but being movable longitudinally of the housing between the housing projections when the plunger and housing are in a different angular relation, an inner plunger within the main plunger bearing against the closed outer end thereof, friction means within the housing engaging the inner plunger and including a friction member seated against the closed end of the housing and lying partly within the inner end of the main plunger, spring means within the main plunger and housing exerting its force at one end against the closed end of the main plunger and at its other end against a part of the friction means, means on that portion of said friction member which lies within the inner end of the main plunger engageable with the internal shoulders on the main plunger to connect the main plunger and said friction member for rotational movement in unison, while permitting their relative longitudinal movement, and interengaging means on said friction member and housing normally preventing relative rotational movement of the friction member and housing.

2. A buffer comprising a housing open at one end andclosed at the other end and having circumferentially-spaced inward projections at its open end, a hollow main plunger extending through the open end of the housing, the plunger having a closed outer end and circumferentiallyspaced outward projections and circumferentially-spaced internal shoulders within the housing, the plunger projections normally being engageable behind the inward projections of the housing to limit the outward movement of the plunger from the housing when the plunger and housing are in one angular relation but being movable longitudinally of the housing between the housing projections when the plunger and housing are in a different angular relation, an inner plunger loosely mounted within the main plunger, said inner plunger having its outer end closed by a head which bears against the closed outer end of the main plunger and extends laterally beyond the inner plunger at opposite sides thereof, friction means within the housing engaging the inner plunger and including a friction member seated against the closed end of the housing and lying partly Within the inner end of the main plunger, spring means within the main plunger and housing bearing at one end against the inner side of the laterally-extending portions of the head which closes the outer end 0f the inner plunger and at its other end against a part of the friction means, means on that portion of said friction member which lies within the inner end of the main plunger to connect the main plunger and said frictional member for rotational movement in unison, while permitting their relative longitudinal movement, and interengaging means on said friction member and housing normally preventing relative rotational movement of the friction member and housing.

3. A buffer comprising a housing open at one end and closed at the other and having circumferentially-spaced inward projections at its open end, a hollow main plunger extending through the open end of the housing, the plunger having a closed outer end and circumferentially-spaced outward projections and circumferentially-spaced internal shoulders within the housing, the plunger projections normally being engageable behind the inward projections of the housing to limit the outward movement of the plunger from the housing when the plunger and housing are in one angular relation, but being movable longitudinally of the housing between the housing projections when the plunger and housing are in a different angular relation, an inner plunger within the main plunger bearing against the closed outer end thereof, friction means within the housing engaging the inner plunger and including a friction member seated against the closed end of the housing, the end of said friction member remote from the closed end of the housing having an inclined face lying at least in part within the inner end of the main plunger, a ring surrounding the inner plunger and having an inclined surface opposite the inclined surface of said friction member, and friction shoes arranged about the inner plunger and interposed between said friction member and said ring and having inclined faces bearing respectively against the inclined faces of saidifriction member and Said ring, spring means within the main plunger and housing exerting its force at one end against the closed end of the main plunger and at its other end against said ring, ribs on the outer periphery of said friction member extending in a direction longitudinally of the main plunger and at least in part within the inner end of the main plunger, said ribs being engageable with the internal shoulders on the main plunger to connect the main plunger and said friction member for rotational movement in unison, while permitting their relative longitudinal movement, and interengaging means on the friction member and housing normally preventing relative rotational movement of the friction member and housing.

4. A buffer as set forth in claim 1 in which the means on said friction member which connects said friction member and the main plunger for rotational movement in unison are ribs on the outer surface of said friction member which extend in a direction longitudinally of the main plunger.

5. A buffer as set forth in claim 1 having a stop on the main plunger engageable by the open end of the housing to limit the movement of the main plunger into the housing.

GEORGE R. MUNRO.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS' Number Name Date 1,747,238 Gross Feb. 18, 1930 2,430,505 Haseltine Nov. 11, 1947 2,431,376 Dath Nov. 25, 1947 2,434,943 Marsh Jan. 27, 1948 2,434,944 Marsh Jan. 27, 1948 

